
To know about communication within the body
Outline the need for communication systems
within multi-cellular organisms
 State that cells need to communicate with each
other by cell signalling
 State examples of cell signalling
 Define key terms
 Describe secondary messenger systems
 Describe the functions of the adrenal glands

 What
conditions do you need to consider for
efficient enzyme action?
 Internal
Changes
 External Changes
 Co-ordinate activities of different organs
 Endocrine
gland
 Exocrine gland
 Hormone
 Target Tissue
 Endocrine

Secretes hormones directly into the blood
 Exocrine

gland
gland
Secretes molecules into a duct which carries
them to where they are used
 Hormone

Molecules released by endocrine glands directly
into blood. Act as messengers carrying signal
from endocrine gland to target tissue
 Target

Tissue
Possess specific receptor on their plasma
membrane. Shape of receptor is complementary
to the shape of the hormone molecule.
 Cell

Nervous System



Signalling
Neurones & Synapses
Rapid
Hormonal System



Hormones carried in blood
Only recognised by target cells
Longer term responses
 Draw
round a member of your group
 Cut out the different glands and place them
where you think they are in the body
 Label them
 Task:


One person will describe what they see
The other person will draw
 Task:
each draw labelled diagram of cAMP
 Adrenal


Responds to stress e.g. pain or shock
Widespread effect as most cells have receptors
for adrenaline
 Adrenal

Medulla
Cortex
Makes steroid hormones
Task: use p23 to add 2 specific
examples of the roles of AM & AC
Plenary
 Adrenaline
binds to receptor on target cell
 Adrenaline first messenger
 Adrenaline can’t enter the cell
 Changes shape of Adenyl cyclase inside cell
 Activates adenyl cyclase
 Changes ATP into cAMP
 cAMP second messenger
 cAMP activates enzyme in the cell
 See
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